1. Field of the Invention
The present invention relates to a method for manufacturing a hybrid integrated component having at least two MEMS (microelectromechanical) system elements, at least one ASIC element being assigned to each.
2. Description of the Related Art
Components having MEMS elements have been manufactured in mass production for many years for greatly varying applications, for example, in the fields of automotive engineering and consumer electronics. The miniaturization of the components is increasingly gaining in significance. On the one hand, the miniaturization substantially contributes to reducing the manufacturing costs of the components and therefore also of the terminal equipment. On the other hand, in particular in the field of consumer electronics, more and more functions—and therefore components—are to be accommodated in the terminal equipment, while the terminal equipment itself becomes smaller and smaller. Therefore, less and less space is available on the application circuit boards for the individual components.
Various miniaturization concepts for sensor components are known from practice, which provide an integration in one component of the sensor function implemented by micromechanics and the circuitry-wise processing and evaluation of the sensor signals. In addition to the lateral integration of the MEMS function and the ASIC function on a shared chip, there are also already concepts for so-called vertical hybrid integration, according to which a chip stack is formed from ASIC, MEMS, and a cap wafer.
Such a vertically integrated component and a method for the manufacture thereof are described in US Patent Application Publication No. 2011/0049652 A1. The known method provides bonding the starting substrate for the MEMS element on an already processed ASIC substrate. A micromechanical structure is only produced thereafter in the MEMS substrate. Independently thereof, a cap wafer is structured and prepared for the mounting over the micromechanical structure of the MEMS substrate and on the ASIC substrate. The cap wafer thus processed is bonded on the ASIC substrate after the structuring of the MEMS substrate, so that the micromechanical structure is enclosed hermetically sealed between the ASIC substrate and the cap wafer.
The known component concept allows cost-effective mass production of robust components having a micromechanical function and a signal processing circuit, since here not only the individual component parts—MEMS element, cap, and ASIC—are manufactured in the wafer composite, but rather also their assembly is implemented to form a component on the wafer level. The MEMS functions and the ASIC functions may be tested at the wafer level, and even the calibration of the individual components may take place at the wafer level. The stacked structure of the known components also contributes toward a reduction in production costs since these components require only a comparatively small mounting area in the second level assembly.